Effect of L-glutamine and L-alanyl-L-glutamine supplementation on the response to delayed-type hypersensitivity test (DTH) in rats submitted to intense training

Abstract

Intense training and exhaustive exercise may cause immunesupression in athletes by reducing plasma glutamine concentration. Initially, this study verified the effect of L-glutamine and L-alanyl-L-glutamine supplementation on the response to delayed-type hypersensitivity test (DTH) in rats submitted to intense swimming training for six weeks. Later on, we assessed the effect of these nutritional interventions on total and differential white blood cell counts and on concentration of anti-bovine serum albumin IgG antibodies, in animals submitted to exhaustion test and a three-hour recovery period. There was no effect of training and supplementation on the response to DTH. Supplemented animals presented greatest plasma glutamine concentration (p<0.05), though this increase in glutaminemia did not interfere on the serum IgG antibody concentration. The recovery period after intense exercise resulted in decreased glutaminemia as compared with the values obtained immediately after exhaustion test (p<0.05). Increase in corticosterone levels induced by strenuous exercises led to leukocytosis, neutrophilia and lymphopenia in post-exercise period (p<0.05). The present study does not confirm the hypothesis that changes in plasma glutamine concentration induced by both supplementation and exercises influence on the response to DTH or for serum IgG antibody concentration in rats submitted to training.